NEW YORK — This winter, as he mended his latest elbow injury, Jenrry Mejia shuttled between the Dominican Republic and the Mets’ complex in Port St. Lucie, Fla. In the DR, he would run and throw daily to get into shape. In Florida, he rehabbed.

Twice, he ran into Terry Collins, who offered him a message: relax. While Mejia saw himself working hard to prepare for the upcoming season, the Mets saw an injury-prone young pitcher.

Mejia, 24, has always been talented but that skill has been overshadowed by a string of surgeries, doctors visits, and other maladies.

Yet, as he showed Monday night in the Mets’ 2-0 win over the Cardinals, when able to take the mound, Mejia can dominate. A popped blister on the middle finger of his right (throwing) hand had forced him to leave his last start early, but was no issue against St. Louis.

"It was an outstanding job because we weren’t sure what he was going to give us," Collins said. "And he gave us more than we expected, for sure."

Buoyed by two runs cobbled together against Cardinals starter Tyler Lyons, the Mets gave Mejia enough of a buffer to earn the win.

Over 6⅔ scoreless innings, Mejia baffled the reigning National League champions. Mixing a mid 90s fastball with a slider and curveball, he struck out seven hitters while giving up just four hits. His command, a trouble spot this season, was a non-issue until the seventh inning, when he walked two batters.

And the blister was a non-factor.

Mejia had applied a topical cream to the finger every other day since his start last Tuesday. While Collins called it a "concern," the pitcher did not share it. As he threw in the bullpen before his start, Mejia was asked how it felt. "It’s good," he responded. "Don’t worry about it."

With that, the Mets’ fears seemed allayed. By the end of the night his ERA had dipped to 1.99 and a string of scoreless innings had risen to 13⅔ over his last three starts.

For Mejia, the key was his control. He had come into the start allowing more than six walks per nine innings, but on this night, he allowed just one through six innings.

When he walked two consecutively in the seventh, with two outs, Collins summoned lefthander Scott Rice out of the bullpen.

Rice, like the group itself, has been uneven this season. The Mets entered the game with the ninth highest ERA in baseball. Rice had a 9.00 ERA.

Yet, he retired Shane Robinson to end the inning, then struck out Matt Carptenter to begin the eighth.

To get through the game, Collins would need to patch together enough relievers to avoid the mines in the Cardinals lineup.

"It all starts with starting pitching," Collins had said before the game. "If he gets you deep in the game you can mix and match."

Carlos Torres was the next in and gave the Mets a bridge to the ninth, striking out Matt Holliday and Matt Adams to escape the inning after allowing a double to Allen Craig.

It made for another successful appearance. After allowing three walks in his first two appearances, Torres has now given up just one earned and two walks in the past 11⅓ innings, while striking out 15.

He has worked his way into high-leverage situations as Collins has restructured his bullpen. Kyle Farnsworth has been a beneficiary, earning a new role as the closer and he finished the game for his first save with the Mets.

"Our bullpen has done a good job," Collins said. "After that first series, where I’m not sure what happened, they’ve settled down and thrown the ball with much more command of their stuff than they did early. They’ve pitched very well lately."